In principle, there are already a large number of different individual technical solutions known as active or as passive braking systems for roller shutter and blind drives. Drives with active electromagnetic or electromechanical brakes use additional energy and generate significant switching noise during actuation. In addition, these require a relatively large installation space, as is apparent from EP 2,234,245 and DE 202005007921 (U). The advantage of a passively functioning braking system lies in the fact that it needs no auxiliary energy and requires a smaller installation space.
US2007/0080033(A1) describes a centrifugal brake comprising a brake drum at least partially overlapping the rotational element and comprising at least one centrifugal shoe, which is essentially radially moveable between the rotational element and an inner wall of the brake drum and is arranged on the rotational element. An additional braking unit is provided, which is triggered by the rotational element upon exceeding a predetermined rotational speed. By this means, the rotational element may be brought to a stop relatively quickly. Such brakes do not generally function directly for a strong or rigid locking of a rotational speed, but instead only limit the same. The centrifugal shoes begin to move radially outward from the rest position beginning at a specific rotational speed due to the centrifugal force affecting them. Upon reaching a specific switch-on rotational speed, the centrifugal shoes come into contact with the brake drum such that friction, and a braking effect connected thereto, occurs. In specific applications, the brake drums also function to stop the rotational element.
A brake unit for a rod-like element is known from U.S. Pat. No. 4,216,848, in which the centrifugal shoes may be brought into contact with a so-called brake shoe such that the latter rotates and moves axially on the rod. A brake wheel is thereby pressed against a brake disk and by this means the rod-like element is ultimately braked.